“There was a huge congratulatory email that came from our publisher and (High Times’ longtime legal counsel) Michael Kennedy,” Bernstein said April 16 from Denver Mart, where the Cup will take root from April 19-20. “This is something we’ve only dreamed of, and the fact that we’re exceeding our dreams, we are just jubilant.”

The sellout is big news for the event. The magazine broke all existing Cannabis Cup records in 2013 when they packed an estimated 10,000-15,000 people into Denver’s Exdo Event Center for the U.S. Cup. This year’s sellout, at a significantly larger venue, guarantees that the event will at least double in size, and Bernstein estimates 37,000 participants will take part over the two days.

“We’ve already opened up additional parking lots to accommodate the groups,” Bernstein said. “And we’re using a lot of space outside of Denver Mart, too. It looks like we’ll have more than 500 booths outside.”

Many attendees have asked if there will be on-site smoking at the Cup, given Denver’s strict laws on public consumption. Bernstein and her colleagues are emphatically letting fans know that, “Yes, it’s a private event with smoking.

“At 4:20 on 4/20 they’re expecting the largest smokeout of its kind. If you were to fly over Denver at that moment I’m sure you’d see huge plooms of smoke and 30,000 happy people.”

So why is the Denver-rooted Cup more popular and successful than its companion Cups in Seattle, Los Angeles, San Francisco and elsewhere? Colorado is home to the first (and only) legal recreational sales in the U.S., of course. But it’s bigger than Colorado, Bernstein said.

“It’s because of the American population that is really giving us the boost that we need,” she said. “Everybody is supporting legalization — and High Times, too. The fact that everybody is pulling together and celebrating this historic milestone with so many people from all over the world, and it’s happening in Denver, it really puts Colorado in a great light.”

Ricardo Baca is the founder and editor of The Cannabist, legal marijuana's paper of record and a division of The Denver Post. Fortune magazine ranked Baca as one of the seven most powerful people in American cannabis while the Brookings Institution...